Natural Science Flashcards
Sci and tech
1
Q
what is an element?
A
- a pure substance
* only has one kind of atom
2
Q
can an element be broken down into simpler substances?
A
No
3
Q
What symbols do we use to write an elements name?
A
1 or 2 letters
4
Q
What is a compound?
A
- a pure substance
* has 2 or more kinds of atoms
5
Q
How can a compound be broken down into its elements?
A
By reactions such as
- heating &
- electrolysis
6
Q
Each compound has a chemical formula.
What does this formula show?
A
- Which elements are present in the compound
- and how many atoms of each element there are in one molecule
EG. Water is H2O
7
Q
What 3 things can the elements be classified into?
A
- Metals
- Non Metals
- Semi - Metals
8
Q
Which metal is not a solid?
What state is this metal?
A
Mercury is liquid
9
Q
Which elements are good conductors of heat and electricity?
A
Metals
10
Q
Complete the sentence:
Metals have high…………
A
boiling and melting points
11
Q
In what state are non-metals
A
solids or gases
12
Q
Are non - metals good conductors of heat?
A
No
13
Q
In what state are semi - metals?
A
solids
14
Q
How does silicon (Si) have properties of a non-metal and a metal?
A
It is shiny like a metal.
It is a poor conductor of heat and electricty like a non-metal.
15
Q
On the Periodic Table; why are the rows labeled Period 1, Period 2, etc?
A
All the elements in a period have the same number of orbitals for their electrons.
eg) Period 1: each element has 1 orbital for its electron
Period 2 : each element has 2 orbital for its electrons
16
Q
What is the maximum number of electron orbitals for each element?
A
7
17
Q
Why are the elements on the Periodic tabled labelled into grouped coloums :1, 2, 3, etc
A
The elements in each group have the
same number of electrons
in the outermost orbital of electrons.
18
Q
Why do the elements in each group have similar chemical properties?
A
They have the same number of gaps in their outer orbital of electrons that can be filled.
19
Q
Why are noble gases stable?
A
They do not react easily with other elements as their outermost orbital is already full of electrons
20
Q
What information is given in each elements block on the Periodic table?
A
- The elements symbol
- The elements name
- The atomic number of the element
- The atomic mass of the element
21
Q
What is the formula for a molecule of Oxygen?
A
O2
22
Q
What does the formula for Oxygen (O2) tell us?
A
one molecule has 2 Oxygen atoms
23
Q
What is the symbol for Hydrogen
A
H
24
Q
What is the symbol for Helium
A
He
25
What is the symbol for Lithium
Li
26
What is the symbol for Beryllium
Be
27
What is the symbol for Boron
B
28
What is the symbol for Carbon
C
29
What is the symbol for Nitrogen
N
30
What is the symbol for Oxygen
O
31
What is the symbol for Neon
Ne
32
What is the symbol for Sodium
Na
33
What is the symbol for Magnesium
Mg
34
What does the symbol this symbol stand for?
Al
Aluminium
35
What does the symbol this symbol stand for?
Si
Silicon
36
What does the symbol this symbol stand for?
P
Phosphorus
37
What does the symbol this symbol stand for?
S
Sulfur
38
What does the symbol this symbol stand for?
Cl
Chlorine
39
What does the symbol this symbol stand for?
Zn
Zinc
40
What does the symbol this symbol stand for?
Cu
Copper
41
What does the symbol this symbol stand for?
Fe
Iron
42
What does the symbol this symbol stand for?
K
Potassium
43
What does the symbol this symbol stand for?
Ca
Calcium
44
```
NaCl:
Sodium Chloride (table salt) is made up of which elements?
```
Sodium (Na) and Chlorine (Cl)
45
Hydrogen sulfide is made up of which elements?
Hydrogen and sulfur
46
What are the elements that make up MgO
Magnesium and Oxygen
47
What does the second part of the compounds name tell us?
what group of atoms are attached to the main atom
48
what is the common name for H2O
Water
49
What is the common name for Sodium Chloride
Salt
50
What is the common name for NaHCO3
Bicarbonate of Soda
51
What is the common name for HCl
Pool acid or Hydrogen Chloride
52
What does the prefix Mono mean
one
53
What does the prefix Di or Bi mean
two
54
What does the name Carbon monoxide tell us?
Each atom of carbon (C) in the compound has combined with one atom of Oxygen (O)
55
What does the name Carbon Dioxide tell us?
Each atom of carbon (C) in the compound has combined with two atoms of Oxygen (O)
56
What does the name Sulfur trioxide tell us?
Each atom of Sulfur (S) has combined with 3 atoms of Oxygen (O)
57
Write the formula and name the compounds for....
2 Hydrogen atoms and 1 oxygen atom
H2O
Hydrogen Oxide (Water)
58
Write the formula and name the compounds for....
2 Oxygen atoms
O2
Oxygen
59
Write the formula and name the compounds for....
one copper atom and 1 Oxygen atom
CuO
Copper Oxide
60
Write the formula and name the compounds for....
1 Sodium atom and 1 chlorine atom
NaCl
Sodium Chloride
61
Write the formula and name the compounds for....
one sulfur atom and 3 oxygen atoms
SO3
Sulfer Oxide
62
Explain the chemical formula for
MgO
1 Magnesium atom and
1 Oxygen atom
(Magnesium Oxide)
63
Explain the chemical formula for
CaCO3
1 Calcium atom
1 Carbon atom
3 Oxygen atoms
(Calcium carbonate)
64
compounds are formed when .....
2 or more elements join together during a chemical reaction
65
In what 2 ways can we show the chemical reaction?
By making models
| By drawing symbols
66
What are reactants?
the different elements that react with each other to form the product
67
What is the product?
the compound that is formed after 2 or more elements have reacted
68
What is the number in the chemical formula called?
the subscript number
69
What gases does Air consist of?
Nitrogen
Oxygen
Carbon dioxide
(and other gases)
70
What is the process of burning called?
combustion
71
When metals react with oxygen, they form....
metal oxides
72
What is the product of Iron burnt in air
iron oxide
73
Write the chemical formula for magnesium burnt in air
2Mg + O2 = 2MgO
74
What is corrosion?
The reaction of the surface of a substance such as metal with air, usually to form an oxide
75
When do metals corrode faster?
If they are wet
or
if air contains acid pollutants such as sulfur dioxide (SO2)
76
Why / When does rust form on the surface of iron?
When it is exposed to air and moisture
77
Why is steel used more often than other metals in many modern constructions?
It is strong and relatively cheap
78
Why does steel rust and corrode easily?
Steel consists mostly of iron
79
Why is rust a problem in construction?
Rust can seriously damage and weaken iron and steel structures and equipment
80
How are iron and steel structures protected from rust?
By painting or plating them with other metals such as
zinc, tin, nickel and chronium.
(which do not corrode with air)
81
What is electrolysis
breaking down of chemical substances by passing an electric current through a solution of them
82
What is the problem with painting the surface of iron and steel with an oil based paint to prevent rust?
The layer of paint can scratch easily, exposing the metal to air and moisture, causing the metal to rust and the paint to peel off.
83
When coating iron or steel with a thin layer of chromium or zinc to prevent rust, what do we call this?
electroplating
84
Iron coated with zinc is called _________ iron?
galvanized iron
85
Give examples of items that have been galvanized?
roofs, shovels, wheel barrows
86
Give examples of items that have been electroplate.
metal parts of motor cars, motorbikes and bicycles
87
What metal will be electroplated with which metal to make jewelry and cutlery
Nickel electroplated with silver
88
What metal will be electroplated with which metal to make metal canned food products?
Steel electroplated with Tin
89
What is formed when non-metals react with oxygen?
non-metal oxides
90
Why do non-metals such as carbon and sulfur react very slowly in air and take a long time to form the non-metal oxides?
Because air only contains 21% oxygen.
91
What is the general equation when any non-metal is burned?
non-metal + oxygen = non-metal oxide
92
what happens when carbon is burnt in air?
What is the chemical equation?
It reacts with oxygen to form carbon dioxide
C + O2 = CO2
93
In what state can non - metal oxides be?
solid , liquid or gas
94
What element does charcoal contain?
carbon
95
What compound is formed when we burn charcoal or wood?
Carbon dioxide
96
Why is carbon dioxide dangerous?
It is poisonous.
| We can not see or smell carbon dioxide.
97
What is the word and chemical equation when sulfur reacts with oxygen?
sulfur + oxygen = sulfur dioxide
S + O2 = SO2
98
How would a scientist collect carbon dioxide or sulfur dioxide?
1. collect pure oxygen from an oxygen tank into a glass jar
2. Heat carbon or sulfur in a spoon until it is burning
3. Quickly transfer the spoon into the oxygen jar
4. Let carbon or sulfur burn until all oxygen has been used up. (stops burning)
99
What colour flame does carbon burn with?
orange - yellow
100
What colour flame does sulfur burn with?
bright blue
101
Why would scientists use pure oxygen to make non - metal oxides?
non - metal oxides burn better in oxygen
102
What are the properties of Acids?
* Taste sour
* Feel rough
* Are corrosive
* Red litmus paper stays red
* Blue litmus paper changes to red
103
What are the properties of Bases?
* Taste bitter
* Feel slippery
* Are corrosive
* Red litmus paper changes to blue
* Blue litmus paper stays blue
104
The pH scale goes from ? to ?
1 to 14
105
What range on the pH scale are acids?
1 to 7
106
What range on the pH scale are bases?
7 to 14
107
What would the pH balance of 7 be called?
a neutral substance
108
What do we use to show us whether a substance is an acid, base or neutral?
chemical indicators
109
Which indicator is most precise in telling us the pH level
| and why?
a Universal Indicator as it shows the full range of pH levels as other indicators only show whether a substance is an acid or a base
110
Is vinegar an acid or a base?
acid
111
Is blood an acid or a base?
neutral
112
Is wine an acid or a base?
acid
113
is baking soda an acid or a base
base
114
Is dishwashin soap an acid or a base?
base
115
What is a neutralization reaction?
when an acid and a base react together
(a base reacting with an acid to make the acid less acidic or neutral)
or
(an acid reacting with a base to make the base less acidic)
116
Explain how brushing our teeth is a neutralisation reaction?
Toothpaste is a base and reacts with the acidic bacteria, neutralising the bacteria that is damaging our teeth.
117
Explain how we treat indigestion with neutralization.
Indigestion is caused by too much acid in the stomach, which is relieved with antacid medicines that contain bases
118
What is hydrochloric Acid (HCl) used for?
* a chemical reagent in the production of plastics
* to remove rust or iron oxide from steel
* in household cleaning substances
* the production of food substances
* leather processing
* neutralising chemicals in swimming pools
119
Where is Sulfuric acid (H2SO4) used?
* in motor car batteries
120
Are non-metal oxides such as carbon dioxide and sulfur dioxide acids or bases?
acids
121
Are metal oxides such as iron oxides and magnesium oxide acids or bases?
bases
122
Are metal hydoxides and metal carbonates acids or bases?
bases
123
When any acid reacts with a metal oxide, what products are formed?
a salt and water
124
When non-metal oxides react with water in the atmosphere what is the product?
acid which falls as acid rain
125
how is acid rain formed?
when burning wood or fossil fuels give off carbon dioxide and sulfur dioxide, they react with the water in the atmosphere to form acid, which falls as acid rain.
126
Why is pure rain slightly acidic?
It has impurities from dust particles dissolved in it.
| Carbon dioxide in the air reacts with the water in the rain to form carbonic acid.
127
What are natural sources that give off carbon dioxide into the atmosphere?
forest fires,
respiration by living organisms
volcanoes
decaying of dead organisms
128
why is rain becoming more acidic?
the levels of carbon dioxide in the air is increasing because of peoples activities.
Therefore more carbonic acid is being produced.
129
sulfer dioxide + water =
| sO2 + H2O =
sulfuric acid
| H2SO3
130
Nitrogen dioxide + water =
| NO2 + H2O
Nitric Acid
| HNO3
131
What natural source causes sulfur dioxide, which causes acid rain?
volcanoes
| decaying of dead organisms
132
What human activities causes sulfer dioxide, which causes acid rain?
burning fossil fuels (coal & oil)
burning sulfide oils
burning wood
133
What natural source causes Nitrogen dioxide, which causes acid rain?
Bacterias in soils and oceans
| lightening flashes
134
What human activities causes Nitrogen dioxide, which causes acid rain?
burning fossil fuels (oil in motor cars)
burning wood
use of nitrogen fertilizers
making of synthetic nitrogen
135
what are the consequences of acid rain to the natural environment?
* forests are destroyed, trees can not survive, as well as the habitats of many animals
* acidity in rivers etc effect reproductive cycles and cause deformities to young animals.
136
what are the consequences of acid rain to human made structures?
* marble, sandstone and limestone dissolve easily in acid rain
* it corrodes paints, textiles and metals speeding up the decay and deterioration of buildings and structures
137
what are the consequences of acid rain to peoples health?
* toxic metals are released in the soil which are absorbed through drinking water, crops or animals that people consume.
* chemicals in the air increase respiratory problems.
*
138
why are soils in the eastern parts of South Africa usually slighty acidic?
There is more rainfall
139
what is used in agriculture to neutralize acidic soil?
and why
Limestone (calcium carbonate CaCO3)
* It is a metal carbonate which is a basic
* It gives plants the essential nutrient - calcium
140
Why is it important to reduce the acidity in soil?
1. makes important nutrients more available to plants
| 2. stops elements such as aluminium from being poisonous to plants
141
when metals react with water they tend to form...
metal hydroxides
142
a hydroxide group contains which atoms?
1 oxygen atom and 1 hydrogen atom
143
what is the product when any acid reacts with a metal hydroxide
a salt and water
144
whenever there is the name carbonate, the formula will include....
CO3
| 1 carbon atom and 3 oxygen atoms
145
when an acid reacts with a metal carbonate, the products thats are formed are...
a salt, water and carbon dioxide
146
what is effervescence?
The bubbling of carbon dioxide through a solution
147
when any acid reacts with a metal, what products are formed?
a salt and hydrogen gas
148
How do metals such as sodium and magnesium react with metal?
quickly and violently
149
? & ? are compounds that form hydrogen ions when dissolved in water.
Acids & Bases
150
Alkali is a ?_____ and can dissolve in water.
base
151
pH is the number between 0 – 14 that tells us how ___?___ a water soluble substance is.
acidic or alkaline
152
Acids change the colour of universal indicator towards the _____?________ colours
yellow, orange and red colours.
153
Bases change the colour of universal indicator towards the ?________ colours
purple colours.
154
• Neutral substances (pH 7), changes the colour of universal indicator to
green.
155
Metal + oxygen →
metal oxide
156
Non-metal + oxygen →
non-metal oxide
157
Carbon + oxygen →
carbon dioxide
158
Metal oxide + water →
metal hydroxide
159
Magnesium oxide + water →
magnesium hydroxide
160
Non-metal oxides + water →
acid
161
Example: Carbon dioxide is pumped into a cold drink to make it fizzy. Carbon
dioxide is a non-metal oxide. When it dissolves in the water of the cold drink,
____?______ is formed
carbonic acid
162
acid + metal oxide →
salt + water
163
Acid + metal hydroxide →
salt + water
164
Acid + metal →
salt + hydrogen gas
165
All life is made of
cells.
166
A __?__ is the smallest part of your body.
cell
167
Unicellular are organism made of __?____
a single cell.
168
The __?_____ forms the outer border of the cell.
cell membrane
169
The membrane is selectively permeable.
| • This means that ______?
it controls which materials pass into or out of the cell.
170
___?___ is the jelly-like substance, which fills the cell.
Cytoplasm
171
?_____ contains deoxyribonucleic acid (DNA).
The nucleus
172
?____ contains the information that determines an organisms inherited
characteristics.
DNA
173
?_____ takes place in the mitochondria.
Respiration
174
• Respiration is the metabolic reaction that releases ___?___
energy from glucose.
175
White plant cells usually have one or two large ___?, which store
substances like sugar, salts and water for the cell.
vacuoles
176
A neuron is also known as ?_____
the nerve cell.
177
• The main parts of the human nervous system include
```
the brain,
spinal cord,
nerves,
ears,
nose,
eyes,
skin and
tongue.
```
178
The nose, ears, eyes, skin and tongue are called
___?____
These organs have specific cells that detect stimuli in the environment. These cells
are known as _________
sensory organs.
receptors
179
Health issues of the nervous system
* Deafness
* Blindness
* Short-sightedness
180
• The male sex cells are called
sperm cells
181
The female sex cells are the
egg cells.
182
• These cells need to __? to create a new life
fuse
183
The main parts of the human reproductive system are
the testes,
ovaries and
uterus.
184
The __? is where the baby grows until it is ready to be born.
uterus
185
reproduction processes include
copulation, ejaculation, ovulation, menstruation,
| fertilisation and implantation, growth, cell division and maturation.
186
With asexual reproduction there is
only one parent. The offspring are identical
| to the parent.
187
In some plants, ????_____ can grow into
| a new plant.
a piece of the plant such as a stem, leaf or root
188
Some simple animals like an amoeba, can reproduce by
dividing into two.
189
In sexual reproductions, there are ?__ parents.
two
190
The parents have reproductive organs that make ___?
gametes (sex cells).
| • The gametes are also called sperm cells or egg cells.
191
Life starts when an egg cell and a sperm cell join during
fertilisation
192
The fertilised egg becomes the ?____ and will develop into a new individual.
embryo
193
Puberty normally ends around the age of
18.
194
The pituitary gland and hormones
• This structure is found at the ___? and starts to make hormones
that tell the organs what to do
base of the brain
195
____?_____ start to
| make the reproductive organs active.
Hormones released from the pituitary gland into the blood stream
196
The ?____ make testosterone
testes
197
the ?_____ make oestrogen.
ovaries
198
Male reproductive organs
| • the male reproductive organs are made up of:
1. Penis
2. Sperm duct
3. Testes
4. Scrotum
5. Urethra
199
As the sperm travels down the sperm duct it mixes with fluids from the male
glands.
The mixture of sperm and fluids is known as ?__
semen.
200
The semen travels through the ___? which runs through the penis.
urethra,
201
The following makes up the female reproductive organs:
1. Vagina
2. Uterus
3. Ovaries
4. Oviducts (fallopian tubes)
202
The function of the female reproductive system is to:
1. Provide safe and suitable conditions for the growth of a baby
2. Make egg cells
203
Every ____?____ an egg is released from one of the ovaries.
month
204
The egg moves from the ?_____ along the oviduct to the uterus.
ovary
205
Because the egg cannot move on its own it is swept along the oviduct by the
action of ?___
tiny hairs.
206
Should the egg not be fertilised it will ?____ as it moves through the
uterus to the vagina.
breakdown
207
The vagina is also called the
birth canal.
208
Human reproduction has several stages they are:
1. Ovulation
2. Menstruation
3. Copulation
4. Fertilisation
5. Implantation
6. Pregnancy (gestation)
209
The release of the ripe egg from the ovary is called
ovulation.
210
Fertilisation normally take place in the
oviduct.
211
Woman are more likely to become pregnant while
they are ovulating.
212
While the egg is developing in the ovary, the soft lining of the uterus grows
thicker.it grows
a thick layer full of blood vessels.
213
```
This is in preparation for ____?_____
The wall of the uterus stays thick
for about a week after ovulation. If the eggs are not fertilised, it passes out of
the body through the vagina.
• Menstruation starts a few days later
```
a baby to grow in it.
214
During menstruation the thick layer of blood vessels that line the uterus are
broken down. The blood and lining are released through the vagina.
Menstruation lasts between
four and seven days.
215
The menstrual cycle lasts for roughly ______?, it has three stages
28 days
216
The main aim of the menstrual cycle is to
get the uterus ready for a fertilised
| egg.
217
Before menstruation, the lining of the uterus thickens with a rich supply of
blood vessels and mucus.
• It is needed for
an unborn baby to survive.
218
The bleeding that a female experience is
the lining of the uterus exiting the
| body.
219
Ovulation usually occurs on the day
14.
220
The egg moves into the oviduct, also known as the
fallopian tube.
221
The sperm cell can survive in the woman’s body between
two to three days.
222
The fertilised egg grows and forms a ball of cells. It moves from the oviduct
into the uterus.
• It is now known as an ___?___ and it sinks into the lining of the uterus that
contains many blood vessels.
• This is known as ____?______
embryo
implantation.
223
The embryo keeps growing. During the first two month of development it is
known as an embryo, and for the last even months it is known as
foetus.
224
As the foetus grows it is attached to the uterus wall by the .
placenta
225
The
| placenta supplies the embryo with
food, water and oxygen from the mother’s
| blood.
226
Waste materials made by the embryo and foetus, such as carbon dioxide, are
removed through the
placenta.
227
The ___?____ connects the foetus to the placenta. It transports blood
between the mother and the foetus
umbilical cord
228
The time period from fertilisation until birth is known as
gestation.
229
In humans, gestation is about ?__ weeks. During pregnancy the woman does
not
40
| menstruate.
230
‘contra’ means against and ‘conception’ means fertilisation therefore
contraception is to ?___
prevent fertilisation
| This is called birth control.tion.
231
STDs are passed from one person to another when they
have sexual contact
| with an infected person.
232
Plants and animals look different from each other this is because
their cells
| are different.
233
A group of tissues make up an
organ
234
?___ are cells that have not yet developed and have the capacity to
specialise into almost any type of cell in the human body.
Stem cells
235
Adult cells can be collected from
blood, adipose or fat tissue and bone
| marrow
236
?_____ are harvested from the blood that is in the umbilical cord
when a baby is born.
Umbilical stem cells
237
Embryonic stem cells are harvested from
human embryos.
238
The most basic organism consists of cells, which group together to form
Tissues
239
?___ system circulates blood though out your body with the help of
the heart, blood and blood vessels.
The respiratory
240
The main function of the respiratory system is to
supply oxygen to all the parts
of your body when we breathe in and release carbon dioxide when we
breathe out.
241
The ?_____ system is a series of organs that converts food into smaller
components so that nutrients can be easily absorbed by the body and
eliminates unused waste material.
digestive
242
• The urinal system is also known as the .
renal system
243
The ? system is the control centre of the human body.
nervous
244
? system is responsible for the movement of the human body
The muscular
245
The ?___ system breaks down food into dissolved nutrients that can be
absorbed into the blood stream and transported to cells throughout the body.
digestive
246
?____ is a nutrient which nourishes the body.
Glucose
247
Structure of digestive system
| • The main components include
the mouth, oesophagus, stomach, intestines
| and liver.
248
• Ingestion- is the
consumption of food by biting, chewing and swallowing
249
• Digestion- is the mechanical and chemical process
that changes food into
| soluble nutrients.
250
• ?____- happens when the soluble nutrients are taken up by the blood
stream the intestines.
Absorption
251
? ____-occurs when undigested food materials, called faeces, are passed
out of the body through the anus
Egestion
252
Ulcers, anorexia nervosa, diarrhoea, liver cirrhosis are health issues of the
digestive system.
253
• The main parts of the circulatory system are the
heart, blood vessels and
| blood.
254
Humans have a closed blood system.
| • This means that
the blood flows around the body contained in blood vessels.
255
Arteries are blood vessels that transport blood
away from the heart.
256
Arteries branch into very small blood vessel called
capillaries
257
The walls of the capillaries consist of a single layer of cells, which allow
gases
| and nutrients to pass through them easily.
258
?______• pass from the blood across the capillary walls into the
cells.
Nutrients and oxygen
259
•___?____ remove the carbon dioxide and other waste substances from the
cells.
The veins
260
Main processes of the circulatory system
• Circulating blood between the heart and the lung
261
The blood that goes from
the heart to the lungs is low in ?
but rich in ?
oxygen
| carbon dioxide
262
The blood that returns to the heart is rich in
oxygen
263
The heart pumps oxygen rich blood from the lungs to
all living cells.
264
High blood pressure, heart attack, stroke are health issues of the
circulatory
| system.
265
Heart rate
| • It is the
number of times a heart beats per minute.
266
The respiratory system
supplies oxygen to the body and for removing carbon
| dioxide.
267
The main parts of the respiratory system include the
nose, mouth, trachea,
| lungs and blood.
268
The trachea is the tube through which
the air travels to the lungs.
269
It splits into the right and left __? which branch into smaller tubes.
bronchi
270
• Breathing involves of two processes:
inhalation and exhalation.
271
When breathing in the muscles in the ?_____ contract air is drawn into the
lungs.
thorax
272
When breathing out the muscles ?_____, and air is forced out of the lungs
relax
273
Breathing occurs because of ?_____ difference between the air in the
lungs and the air outside the body.
air pressure
274
Gaseous exchange occurs in the ?___ of the lungs.
alveoli
275
?_____ is the movement of molecules from an area where they are in high
concentration to an area where they are in a low concentration.
Diffusion
276
The __? protects the body, provides support and enables movement.
skeleton
277
?____ work together to create body movement.
Muscles and bones
278
Structure of the musculoskeletal system
| • The main parts are
muscles, bones, cartilage, tendons and ligaments.
279
Bones are attached to muscles by
ligaments.
280
Ligaments are flexible and prevent
dislocations of bones.
281
Joints are found where
two or more bones meet in the body.
282
• The main processes of the musculoskeletal system are:
1. Contraction and relaxation of muscles.
| 2. Movement and locomotion.
283
Muscles are made up of cells called
muscle fibres
284
?____ directs messages to the muscles to contract or relax.
The brain
285
Musculoskeletal muscles work in ?
pairs.
286
Rickets, osteoporosis, arthritis are health issues of the
musculoskeletal
| system.
287
The ? systems remove’s waste from the blood and regulates the
body’s fluids.
excretory
288
The excess water needs to be removed from the body. This is known as
osmoregulation.
289
Structure of the excretory system
| • The main components are
kidneys, bladder, and ureter
290
Main process of the excretory system
| • These processes include
filtration, absorption, diffusion and excretion.
291
Filtration
• Filters separate the ?
• The waste products and excess water is now called a ?
• The filtrate ends up in small tubes inside the ?
• The blood which leaves the kidney is now purified of waste products.
* waste products and a part of the water from the blood
* filtrate..
* kidney.
292
2. Absorption
| • The main useful substances which are still in the filtrate such as ? , ? & ?get absorbed from the filtrate.
water,
| glucose, and amino acids
293
3. Diffusion
• The waste products that are still in the blood diffuses from the blood into the
small tubes with the filtrates.
294
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4. Excretion
• When all three processes have been completed, the fluid in the tubes is
known as
• These small tubes conduct the ________
•
```
•
urine.
| urine to the ureter.
295
The ureter conducts the urine to the
bladder.
296
From the bladder, the urine leaves the body by means of the
urethra.
297
• Kidney failure, bladder infection, kidney stones are health issues of the
excretory system
